A derogatory phrase expressing incredulity at the lack of understanding on the part of someone else, as in “Was I not speaking clearly enough for you?” “Did you not understand what I just said?” "What is wrong with you?"

A derogatory term expressing incredulity at the lack of understanding on the part of someone else, as in “Was I not speaking clearly enough for you?” “Did you not understand what I just said?” "What is wrong with you?"